Our results suggest a significant impact of this targeted preventive intervention on HIV/STI prevalence among FSWs. The recent increase in gonorrhea prevalence could be related to the lack of integration of the intervention components.

BackgroundA comprehensive, HIV prevention programme (Projet Sida1/2/3) was implemented among female sex workers (FSWs) in Cotonou, Benin, in 1993 following which condom use among FSWs increased threefold between 1993 and 2008 while FSW HIV prevalence declined from 53.3% to 30.4%.ObjectiveEstimate the potential impact of the intervention on HIV prevalence/incidence in FSWs, clients and the general population in Cotonou, Benin.Methods and FindingsA transmission dynamics model parameterised with setting-specific bio-behavioural data was used within a Bayesian framework to fit the model and simulate HIV transmission in the high and low-risk population of Cotonou and to estimate HIV incidence and infections averted by SIDA1/2/3. Our model results suggest that prior to SIDA1/2/3 commercial sex had contributed directly or indirectly to 93% (84–98%) of all cumulative infections and that the observed decline in FSWs HIV prevalence was more consistent with the self-reported post-intervention increase in condom use by FSWs than a counterfactual assuming no change in condom use after 1993 (CF-1). Compared to the counterfactual (CF-1), the increase in condom use may have prevented 62% (52–71%) of new HIV infections among FSWs between 1993 and 2008 and 33% (20–46%) in the overall population.ConclusionsOur analysis provides plausible evidence that the post-intervention increase in condom use during commercial sex significantly reduced HIV prevalence and incidence among FSWs and general population. Sex worker interventions can be effective even in medium HIV prevalence epidemics and need to be sustained over the long-term.

Objectives-During the 2008 HIV prevalence survey carried out in the general population of Cotonou, Benin, face-to-face interviews (FTFI) were used to assess risky behaviours for HIV and other sexually transmitted infections (STI). We compared sexual behaviours reported in FTFI with Corresponding author: Dr. Michel Alary, Centre de recherche du CHU de Québec, Hôpital du Saint-Sacrement, 1050 Chemin Ste-Foy; G1S 4L8, Québec (Québec), CANADA, malary@uresp.ulaval.ca. Competing interestsThere is no conflict of interest Authors' contributions LB was involved in the study design and participated in the data collection, managed the data and had the main responsibility for data analysis and drafted the manuscript. SD contributed significantly to data analysis and preparation of the manuscript. IM was in charge of data collection and reviewed critically the content of the manuscript. CML, AB, MCB and ACL were involved in the study design and contributed significantly to the preparation of the manuscript. SA and DMZ were involved in the study design and reviewed critically the content of the manuscript. MA was responsible for the overall study design, guided the data analysis and contributed significantly to the preparation of the manuscript. All authors approved the final version of the manuscript.Licence statement: The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive licence (or non-exclusive for government employees) on a worldwide basis to the BMJ Group and co-owners or contracting owning societies (where published by the BMJ Group on their behalf), and its Licensees to permit this article (if accepted) to be published in Sexually Transmitted Infections journal and any other BMJ Group products and to exploit all subsidiary rights, as set out in our licence. http://group.bmj.com/products/journals/instructions-for-authors/licence-forms

ObjectiveTo assess changes in the prevalence of HIV and other sexually transmitted infections, as well as in different proximal and distal factors related to HIV infection, in the general population of Cotonou between 1998 and 2008, while an intensive preventive intervention targeting the sex work milieu was ongoing.MethodsA two-stage cluster sampling procedure was used to select the participants in each study. Subjects aged 15–49 who agreed to participate were interviewed and tested for HIV, syphilis, HSV-2, gonorrhoea and chlamydia. We used the Roa-Scott Chi-square test (proportions) and the Student’s t test (means) for bivariate comparisons, and adjusted logistic regression models taking into account the cluster effect for multivariate analyses.ResultsHIV prevalence decreased significantly in men (3.4% in 1998 versus 2.0% in 2008, p = 0.048), especially in those aged 15–29 (3.0% to 0.5%, p = 0.002). Among men, the prevalence of gonorrhoea decreased significantly (1.1% to 0.3%, p = 0.046) while HSV-2 prevalence increased from 12.0% to 18.1% (p = 0.0003). The proportion of men who reported condom use at least once (29.3% to 61.0%, p<0.0001) and of those having attained a secondary educational level or more (17.1% to 61.3%, p<0.0001) also increased significantly. There was an overall decrease in the prevalence of syphilis (1.5% to 0.6%, p = 0.0003).ConclusionThis is the first population-based study reporting a significant decline in HIV prevalence among young men in an African setting where overall prevalence has never reached 5%. The decline occurred while preventive interventions targeting the sex work milieu were ongoing and the educational level was increasing.

The aim of this study was to identify correlates associated with condom use at last intercourse between sex workers (SW) and their boyfriends (BF). The sample was derived as a convenience sample recruited through existing HIV prevention organizations in Benin, Guinea and Senegal. The Theory of Planned Behavior served as the conceptual framework. A total of 406 individuals (220 SW and 186 BF) participated in the study. Socio-demographic, behavioral and psychological variables were collected through a face-to-face administered questionnaire. Condom use at last intercourse was significantly associated with intention and perceived control among SW as well as their BF. With respect to intention, perceived control, attitude and moral norm explained 82 and 74% of intention of SW and BF, respectively. These results suggest that promoting condom use among SW and BF should be based primarily on the development of personal ability to overcome obstacles to condom use.